LU-4597 clio: clear nowait flag agl lock re-enqueue

LU-4597 clio: clear nowait flag agl lock re-enqueue

The LDLM_FL_BLOCK_NOWAIT flag should be cleared when re-enqueue
the agl lock as normal glimpse, otherwise, it won't get size back
if there is conflicting locks on other client.

Lustre-change: http://review.whamcloud.com/9249
Lustre-commit: 85c352274b3435a41649e9a5089da83b54893d37

Change-Id: I421d033496b57fb3d24635587112eaab3ba2ea32
Signed-off-by: Niu Yawei <yawei.niu@intel.com>
Reviewed-on: http://review.whamcloud.com/9328
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>